Method constructor

src/openlayers/mapping/Tianditu.js:30–94

(opt_options)

 */
export class Tianditu extends WMTS {
  constructor(opt_options) {
    var layerLabelMap = {
      "vec": "cva",
      "ter": "cta",
      "img": "cia"
    }
    var layerZoomMap = {
      "vec": 18,
      "ter": 14,
      "img": 18
    }
    var options = opt_options || {};
    var attributions = options.attributions || "Map Data <a href='https://www.tianditu.gov.cn' target='_blank'><img style='background-color:transparent;bottom:2px;opacity:1;' " +
    "src='https://api.tianditu.gov.cn/img/map/logo.png' width='53px' height='22px' opacity='0'></a> with " +
    "<span>© SuperMap iClient</span>"
    options.layerType = options.layerType || "vec";
    options.layerType = options.isLabel ? layerLabelMap[options.layerType] : options.layerType;
    options.matrixSet = (options.projection === 'EPSG:4326' || options.projection === 'EPSG:4490') ? "c" : "w";
    if (!options.url && !options.urls) {
      options.url = "https://t{0-7}.tianditu.gov.cn/{layer}_{proj}/wmts?"
    }
    if (options.key) {
      options.url = `${options.url}tk=${options.key}`;
    }
    options.url = options.url.replace("{layer}", options.layerType).replace("{proj}", options.matrixSet);
    var tileGrid = options.tileGrid || Tianditu.getTileGrid(options.projection || 'EPSG:3857');

    var crossOrigin = options.crossOrigin !== undefined ? options.crossOrigin : 'anonymous';

    var superOptions = {
      version: options.version || '1.0.0',
      format: options.format || 'tiles',
      dimensions: options.dimensions || {},
      layer: options.layerType,
      matrixSet: options.matrixSet,
      tileGrid: tileGrid,
      style: options.style || 'default',
      attributions: attributions,
      cacheSize: options.cacheSize,
      crossOrigin: crossOrigin,
      opaque: options.opaque === undefined ? true : options.opaque,
      maxZoom: layerZoomMap[options.layerType],
      reprojectionErrorThreshold: options.reprojectionErrorThreshold,
      url: options.url,
      urls: options.urls,
      projection: options.projection || 'EPSG:3857',
      wrapX: options.wrapX
    };
    //需要代理时走自定义 tileLoadFunction，否则走默认的tileLoadFunction
    if (options.tileProxy) {
      superOptions.tileLoadFunction = tileLoadFunction;
    }
    super(superOptions);

    if (options.tileProxy) {
      this.tileProxy = options.tileProxy;
    }
    //需要代理时，走以下代码